It doesn’t come via email. A 90 day report online will send an email but the TM30 is just a static database entry. It’s either filed or it isn’t.
You file online and then go back and search for the filing. As
@T**
mentioned you can only go back 7 days to search. If longer than that file a new one.
Once you find the filing click the little magnifying glass to see your data and near the bottom of the screen there is a button that says “export”. Click that and you’ll get a pdf file that you can print as proof of filing.